Pantographic apparatus for attaching to universal drafting machines



W, A. PERKINS.v PANTOGRAPHIC APPARATUS FOR AIIACHIAIG To UNIVERSAL DRAFIIAIG MACHINES.

APIfLIcATIoN FILED Ammo, 12120E Patented May'9. 1922.

2 SHEETS-SHEET l.

lrlnlQnnl-lnff W. A. PERKINS.

PANTOGRAPHIC APPARATUS FOR ATTACHING T0 UNIVERSAL DPAFI'ING MACHINES.

APPLICATION FILED APR. 30,1920.

Patented May9-1922.

2 SHEETS-SHEET 2.

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" traeineT point.

UNITED ,STATES PATENT T WAYNE ci; resigns, or Hawrnoann, rinviene..

rienroennrnrc T Henares son `Trrr'racailles To `unii/*nasen pasarme amenities.

i PERKINS, of America,

` T wpantographic TTTapparatus for Tattaching to T TT universal T TTdraffting T machines, T for copying,

T reducing, and enlarging drawings; T and l TT do hereby declare the Tfollowlng T to T be T a `T'TTUITlLTTclear,T and TT exact description of the n- T TTTveI-Tition, TsuchfTasTTivillTenable others skilled Tin TT the Tart to Tivhich it TappertainsT to T make and use thesarne. T T

T ,TheT principalTobjectTTofTTiny invention is Tto provide fanT attachment TTT-tor use fin combina T tion T withTthe TTWell hnoWnTTuniversa-l draft- TTyiTngT machine, TvlTTich T attachment niay be Tused TTTiTnTTTtheT same Tmanner T asT the, ordinary pan- ZOTTTtograph but Tvvithlincreased latitudeTTand T T usefulness `dueto the-` adjustable hinged arms 1 Tand other features hereinafter T described.

` Another Tobject otTmyTinventionT s top ro- T T Tvide air T attachment for T use -in combination chine consistingof parallel pairs TTof arms which the range ,oiT-theTTelative Tp0si` T TereetlyT increased berend .that mended bv `the single Tarrns,TTWl1i`ch in conjunction with ,TadjTustaTble pencil T or `tracing point TTholder TTTTgTrive 'furtherTinTcreasedT latitude and useful- Tgness. T T T p Tg Furtherohjects Tot theinvention T are Tto TpTlTToviTdeT a device oTTtlTiisTTclass ,which shall TT possess superior TTadvantages in point Tof T T smpltr, T general eieny, and may T Tbe T used-Tas TaT pantograph Tor drafting machine desired. T T T f T T T TTThe inTTfentionTconSSs oitT adjustahlearins Tpivotallv hinged together ivTiT 1 Topposite ends attached b v means of yolres and clampsfto theT parallel arms Toit the dTiT'agft-ingmachine, .TiviTthT Tprovisi onT Tfor T claspingi aT pencil Tor trac- TTing TpointTatT the centerotthe circular hinge T `T`aTndTa holder arm .insertedTTin the Tusualhead ofTT theT dialftingTTmachineT carrying TT anTTad.- ,T fustahlyTT attached TTholder `T for a T pencil TTTor T 'ons ofTtheTtvvoTTor more drawingscan be T The invention TalsoT Tconsists T oi Tt-Wo pairs ,of parallel adjustableTT armsTTpivotally `T TclaInpedT to Ta ringTbyT means of ,set T screws,

" with opposite ends Tof saiTdTaiT'ms attached Tby T sinTiilar T.naeansto the parallel [arms ofT Tthe Tfdrafting machine, with anTeXtension Tholder T TT farm Tpimtally inserted nT the eine Tearrrng T Specication ofT Letters Patent.

,with f the WellTknownTuniversalqdrating ina- TPatented May `9, 1922.

TTApplicationTledfAprT 30,1920.' Serial No. 3??,8'71.

Tan adjustable pencil or tracingpoint holder, .in combination with a similar-holder arm inserted on the protractor head oi' the draft- Ting machine, also carrying an adjustable pencil or tracing point holder. The invention further consists in the cornwbination with the draftinginachine ot the improved construction, arrangement Tand combination of 1 ia1tsTivhicli` Willi be herein TTTafterT fully described in the speciiicationaiid particularly claiined.

ATYVithTthese and otherende in view, which Willreadily appearTas the nature of the in- T Tvention is betterunderstood and used, l will proceed to idescribe its constructionand op- TTeration, reference beingT had toT the annexed TTdraWing, inTTWhieli,-- T` T T Figure :l Tis Taplan view olT the panto- T graphic device" attached T to the T,universal T drafting Trnachine.

FigTT 2 is a` plan T viewT Tof a the apparatus.

TTFig. 3 isa side elevation TTTonT line l-l of Fig'. T l.

T'Fig-TT4 is a side elevation Toii the apparatus on line 2 2 of Fig. T2. T T T In theT drawing similarreference char- TTacters refer tothe same part Tinall thelvievvs; the parts oi Ithe universal. Tdraitingg machine are referred to byTTletters` and the parts Toi the device TinoreT particularly described and T claimed separately and in combination with T said T universal T draietinp;` machine are shown by figures. 1

TReferringTTto the drawing, the deviceTis moreTTTparticularly described as consisting` o'I Ttvvo arms and 7, Fig. l, adjustable in Tlength,TTattachedTTbv pivoted clamps'llfand 8 T respectively Tto TT yokes 3 and `9 respectively', with TaT cylindrical ring Tand QTTTFTigTl, inT turnare attached by pivoted clamps l, 2, l0 audqll respectivelyT to of the T apparatus arms A, B, C,T and D respectively oli the uni-T holder F oliT the,

Tniodiiication of f means of set screw 23)v toarm 22.

A and B at a point where the ratio of the distance from .bolt a to clamp 1, and bolt al to clamp 2 is to the length of arms A and B as the scale of the smaller drawing is to the scale of the larger drawing, and the distance from bolts a4 and a5 to clamps 10 and 11 are made equal to the distance from bolt a to clamp 1 and bolt a2 to clamp 2 respectively. The length of arm 5 is set equal to they distance from bolt 0, at inner end of arm A to clamp 1 or the distance from bolt a4 to clamp 10, and the length of arm 7 is set equal to the distance from bolt al to clamp 1 thus forming a parallelogram. By

the additional circular movement obtainable through use of protractor head N a much greater latitude in the relative positions of the two drawings is permitted than is obtainable with the ordinary pantograph. When properly set it is seen that any movement of protractor head N or the pointer holder r12 will produce a similar lmovement of the pencil or tracing point at 6, the amount of the latter being in the same ratio to the movement of pointer holder 12 as the length from bolt a on inner end of arm A to clamp 1 is to the length of arm A.

.An important modification of my invention will now be described, This modification consists in the use of two pairs of parallel arms as illustrated in Figs. 2 and 4. The principle of themodilication is the same as in the use of single arms. but by the use of two pairs of arms 1.5, 16, 17 and 18 in place of single arms 5 and 7, the circular yoke 19 willalways be held in a position parallel to itself and the range of the relative positions of the two drawings on which the device is being used can be greatly increased beyond that accomplished by the device illustrated in Figs. 1 and 3. This is accomplished by the use of pencil or tracing point holder 21 adjustably attached by Arm 22 is in turn pivotally attached by means of set screw 2O to circular yoke 19, Fig. 2, and so clamped in any desired position. Arms 15 and 16, Fig. 2 are pivotally attached to circular yoke 24 by clamps 25 and 26, and circular yoke 24C is pivotally clamped to arms A and B by clamps 1 and 2. Arms 17 and 18, Fig. 2 are pivotally attached to circular yoke 27 by clamps 28 and 29, and circular yoke 27 is in turn pivotally clamped to arms C and"D by clamps 10 and 11. Arms 15, 16, 17. and 18 are pivotally attachedr to vcircular yoke 19 by means of clamps 30. 31, 82, and 33 respectively, as is shown in Figs. 2 and et.

In 'the operation of this modifeddevice as shown in Figs. 2 and 1, the same use is madeof it as hereinbefore described, except that 1n place of the singleA arms 5 and 7,

the pairs of arms 15 and 16, and 17 and 18 y must each be set equal to the `distance from bolt a* to clamp 10, and bolt a5 to clamp 11,

proportions only is essential to its etective working.

The universal drafting machine with which this is necessarily made in combination consists of a. frame composed of four arms or bars A, B, C, and l), Figs. 1 and 3. One end of arm A is pivoted to anchor O by means of bolt or screw a, or other suitable means, the other end being pivoted to ring M by means of similar bolt al. The ends of parallel arm B are similarly pivoted to anchor O and ring M by bolts (1,2 and n3 respecirely. Anchor member O is provided with a set screw P for attaching the device to any drawinotable or other appropriate support. Arms (i and D are each pivotally attached to ring M by means of bolts a* and (t5 respectively at one end and the other end is similarly attached to holder frame E by means of bolts a6 and a7 respectively. Circular head or prot-ractor N is attached to holder frame E by means of set screws b1 and b2. Head N is provided with a scale holder arm F. Inserted on scale holder arm F is graduated scale arm 14, which carries adjustable holder 12 clamped securely thereto by means of set screw 13, Fig. 1, which is provided with a hole for insertion of pencil.

Various modification of this device within the scope of the invention and defined in the following claims may be made in the particular construction of the device, and also in the shape and organization of the active members thereof without departing from the spirit of this improvement.

I am aware that the parallel arms or motions of the universal drafting machine and the ordinary pantograph are not new, but it will be noted that the principles of the universal drafting machine and the ordinary pantograph are combined in a novel manner and so arranged as to be capable of being used as either or both, so I do not claim such a combination as described broadly, but having described my invent-ion, what I claimV as new and desire to secure by Letters Patent is- 1. An attachment for a drafting machine having pivotally connected arms, compris ing two arms pivotally connected to each other and having their free ends adapted lo be pivotally secured to the arms of said machine, and means for securing a marking instrument to the pivotal connection between said arms, substantially as described.

2. An attachment for a drafting machine having pivotally connected arms, comprising two arms pivotally connected to each other and having their free ends adapted to be pivotally secured to the arms of said machine, each of said two arms including a pair of parallel rods, a yoke pivotally connecting the ends of one pair of rods to the other,

and yokes for pivotally connecting the free i ends of said arms to the arms of said ma* chine, a graduated scale arm adapted for attachment tosaid first mentioned yoke, a de- `Vice for holding a marking instrument `ally connected arms attached to said yoke,

a protractor head device pivotally connected to the free end of said second pair of arms, a graduated scale arm att-ached to said protractorhead device, an adjustable marking holder mounted'on said scale arm, a third and fourth pair of pivotally connected arms, a second yoke carrying said third and fourth pair of arms, a third and fourth yokerespectively pivotally attached to said first and second pair of arms carrying respectively attached thereto said third and fourth pair of arms, a graduated scale arm attached to said second yoke, an adjustable pencil holder member mounted on said scale arm, and set screw means for holding said parts in adjustable positions, as and for the purpose described.

In testimony whereof I aix my signature in the presence of two Witnesses.

WAYNE A. PERKINS. I/Vitnesses G, B. STANNARD, JOHN GrmL.` 

